Finite Element Analysis of Stress Distribution In Tooth-Implant Retained Prostheses: Impact of Periodontal Support,...

The durability of tooth-implant supported restorations prostheses is significantly influenced by biomechanical factors. Despite advancements in dental implant technology, integrating natural teeth with implants remains a challenge due to their disparate biomechanical properties. This study employed 3D finite element analysis to investigate the impact of periodontal support and the number of teeth and implants on stress distribution within these prostheses.

Six virtual models of tooth-implant retained prostheses were constructed using 3D finite element analysis. These models varied in terms of periodontal support (normal and compromised) and bridge design (three-unit, four-unit with two dental abutments, and four-unit with two implants). A patient's CBCT scan provided the basis for a realistic mandibular bone model. A single ITI implant was utilized, and the teeth and bridge frameworks were designed according to standard metal-ceramic prosthesis principles. Static forces of 250 N were applied vertically and obliquely to assess stress distribution, measured in megapascals (MPa).

Compromised periodontal support significantly increased stress on the implant and bone, particularly under oblique loading. Specifically, stress levels increased by approximately 21% under vertical loading and 24-25% under oblique loading. Conversely, increasing the number of teeth and implants substantially reduced stress on the implant and bone. Oblique forces consistently induced higher stress levels compared to vertical forces.

This study indicates that teeth with a 1:1 crown-to-root ratio are optimal abutments. To minimize stress and reduce the risk of complications, increasing the number of teeth and implants, along with appropriate occlusal adjustments, is recommended.